LED inspection lamp, cluster LED, and LED with stabilizing agents

Abstract

LED inspection lamps and spot lights have a plurality of LED sources. For some, radiation passing through lenses is superimposed in target area at target distance. The LED sources may be a cluster LED having more than one semiconductor die. The LED package may have a domed forward surface forward of each semiconductor die for optical purposes. The domed surface may be designed to work either with or without additional optics. The LED package may be made of epoxy having additives to resist degradation of the epoxy by ultraviolet or visible violet radiation from the LED sources. The package may be made of a material other than epoxy, such as acrylic or another thermoplastic, or a casting resin. The package may have a first, ultraviolet-resistant material that surrounds the LED chip and that is surrounded by a second material which may be epoxy.

What is claimed is:  
     
         1 . An LED lamp comprising: 
 a. an LED source having a plurality of LED chips, each chip producing a beam of radiation, and    b. a plurality of lenses, each lens for capturing a beam of radiation from an LED chip of the LED source,    wherein, the lenses collimate the captured beams of radiation to produce collimated beams of radiation and the lenses merge the collimated beams of radiation at a target distance.    
     
     
         2 . The LED lamp of  claim 1 , wherein the LED source is a LED cluster comprising the plurality of LED chips within a single encapsulant package.  
     
     
         3 . The LED of  claim 2 , wherein the lenses are part of the encapsulant package.  
     
     
         4 . An LED lamp comprising: 
 a. an LED source having a plurality of LED chips, each chip producing a beam of radiation, and    b. a plurality of lenses, each lens for capturing a beam of radiation from an LED chip of the LED source,    wherein, the lenses collimate the captured beams of radiation to produce collimated beams of radiation and the lenses merge the collimated beams on radiation at a target distance, and wherein the LED chips emit radiation including wavelengths of 425 nm or less.    
     
     
         5 . An LED source comprising: 
 a. a plurality of LED chips, each chip produces a beam of radiation,    b. at least one anode for connection, directly or indirectly, between a source of power for the LED source and one of the LED chips,    c. at least one cathode for connection, directly or indirectly, between a source of for the LED source and one of the LED chips, and    d. an encapsulant for encapsulating each of the LED chips, wherein the encapsulated LED chips are part of a single encapsulate package, the radiation from the LED chips is emitted from the encapsulate package, and the encapsulant comprises a UV stabilizing agent; so that, the encapsulant resists degradation by radiation produced from the LED chips, while allowing desired radiation from the LED chips to pass through the encapsulant and exit the LED.    
     
     
         6 . The LED source of  claim 5 , wherein the encapsulant comprises an epoxy.  
     
     
         7 . The LED source of  claim 5 , wherein the stabilizing agent comprises an antioxidant.  
     
     
         8 . The LED source of  claim 7 , wherein the antioxidant comprises a hydrogen donor.  
     
     
         9 . The LED source of  claim 8 , wherein the hydrogen donor comprises a substituted phenol.  
     
     
         10 . The LED source of  claim 9 , wherein the substituted phenol comprises those with substituents in the 4-position.  
     
     
         11 . The LED source of  claim 9 , wherein the substituted phenol comprises those with substituents providing steric hindrance in the 2,6- position.  
     
     
         12 . The LED source of  claim 7 , wherein the antioxidant comprises a hydroperoxide decomposer.  
     
     
         13 . The LED source of  claim 12 , wherein the hydroperoxide decomposer comprises a phosphate.  
     
     
         14 . The LED source of  claim 12 , wherein the hydroperoxide decomposer comprises a phosphonite.  
     
     
         15 . The LED source of  claim 12 , wherein the hydroperoxide decomposer comprises a sulfie.  
     
     
         16 . The LED source of  claim 12 , wherein the hydroperoxide decomposer comprises a dialkyldithiocarbamate.  
     
     
         17 . The LED source of  claim 12 , wherein the hydroperoxide decomposer comprises a dithiophosphate.  
     
     
         18 . The LED source of  claim 7 , wherein the antioxidant comprises a radical scavenger.  
     
     
         19 . The LED source of  claim 18 , wherein the radical scavenger comprises a tetramethyl piperidine derivative.  
     
     
         20 . The LED source of  claim 5 , wherein the encapsulant comprises a light stabilizer.  
     
     
         21 . The LED source of  claim 20 , wherein the light stabilizer comprises a quencher.  
     
     
         22 . The LED source of  claim 20 , wherein the fight stabilizer comprises a non-UV absorber light stabilizer.  
     
     
         23 . The LED source of  claim 20 , wherein the non-UV absorber light stabilizer comprises a substituted tetramethylpiperidine derivative.  
     
     
         24 . The LED source of  claim 23 , wherein the substituted tetramethylpiperidine derivative comprises a sebacate.  
     
     
         25 . The LED source of  claim 24 , wherein the sebacate comprises bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate.  
     
     
         26 . The LED source of  claim 20 , wherein the light stabilizer comprises a UV absorber.  
     
     
         27 . The LED source of  claim 26 , wherein the UV absorber comprises a substituted derivative of benzophenone.  
     
     
         28 . The LED source of  claim 27 , wherein the substituted derivative of benzophenone comprises a hydroxybenzophenone.  
     
     
         29 . The LED source of  claim 28 , wherein the hydroxybenzophenone comprises 2,4-dihydroxybenzophenone.  
     
     
         30 . The LED source of  claim 28 , wherein the hydroxybenzophenone comprises 2,2′-dihydroxy-4,4′-dimethoxybenzophenone.  
     
     
         31 . The LED source of  claim 28 , wherein the hydroxybenzophenone comprises 2-hydroxy-4-methoxybenzophenone.  
     
     
         32 . The LED source of  claim 26 , wherein the UV absorber comprises a substituted derivative of benzotriazole.  
     
     
         33 . The LED source of  claim 32 , wherein the substituted derivative of benzotriazole comprises a phenylbenzotriazole.  
     
     
         34 . The LED source of  claim 33 , wherein the phenylbenzotriazole comprises 2-(2-hydroxy-5-methylphenyl)benzotriazole.  
     
     
         35 . The LED source of  claim 33 , wherein the phenylbenzotriazole comprises 2-(2H-benzotriazol 2-yl)- 4 , 6 -di-tert-pentylphenol.  
     
     
         36 . The LED source of  claim 26 , wherein the UV absorber comprises a substituted hydroxyphenyl triazine.  
     
     
         37 . The LED source of  claim 5 , wherein the encapsulant comprises a polyacrylate.  
     
     
         38 . The LED source of  claim 5 , wherein the encapsulant comprises a styrene.  
     
     
         39 . The LED source of  claim 5 , wherein the encapsulant comprises a carbonate.  
     
     
         40 . The LED source of  claim 5 , wherein the encapsulant comprises an urethane.  
     
     
         41 . The LED source of  claim 5 , wherein the encapsulant comprises an amide.  
     
     
         42 . The LED source of  claim 5 , wherein the encapsulant comprises an acetal.  
     
     
         43 . The LED source of  claim 5 , wherein the encapsulant comprises an olefin.  
     
     
         44 . The LED source of  claim 5 , wherein the encapsulant comprises a copolymer of two or more polyacrylates, styrenes, carbonates, urethanes, amides, acetals and olefins.  
     
     
         45 . The LED source of  claim 5 , wherein the encapsulant package is shaped to produce, for each LED chip, a round beam of the radiation emitted from each LED chip.  
     
     
         46 . The LED source of  claim 5 , wherein the encapsulant package comprises a plurality of lenses forward from the LED chips; and wherein each lens captures a beam of radiation from an LED chip of the LED source, the lenses collimate the captured beams of radiation to produce collimated beams of radiation, and the lenses merge the collimated beams of radiation at a target distance forward of the LED source.  
     
     
         47 . An LED lamp comprising: 
 a. the LED source of  claim 5 ,    b. a plurality of lenses separate from the encapsulant package, and forward from the LED chips,    wherein, each lens captures a beam of radiation from an LED chip of the LED source, the lenses collimate the captured beams of radiation to produce collimated beams of radiation, and the lenses merge the collimated beams of radiation at a target distance.    
     
     
         48 . A LED, comprising: one or more LED chips encapsulated in an encapsulant package, where the one or more LED chips have a peak emission wavelength of less than 425 nm and where the encapsulant is epoxy mixed with a stabilizing agent to resist damage to the epoxy by radiation from the LED chip(s) while allowing desired radiation from the LED chips to pass through the encapsulant and exit the LED.  
     
     
         49 . The LED of  claim 48 , wherein the encapsulant comprises a mixture in which a piperidyl sebacate is combined with at least one of a benzophenone or benzotriazole in the range of 0.01-0.5 percent by weight of the encapsulate.  
     
     
         50 . A light emitting diode having one or more LED chips encapsulated in an encapsulate package, where the LED chip(s) have a peak emission wavelength of less than 425 nm and where the encapsulant is epoxy mixed with a phenolic inhibitor to resist damage to the epoxy by radiation from the LED chip(s).  
     
     
         51 . A light emitting diode having one or more LED chips encapsulated in an encapsulate package, where the LED chip(s) have a peak emission wavelength of less than 425 nm and where the encapsulant is epoxy mixed with a hindered amine light stabilizer to resist damage to the epoxy by radiation from the LED chip(s).  
     
     
         52 . A light emitting diode having one or more LED chips encapsulated in an encapsulate package, where the LED chip(s) have a peak emission wavelength of less than 425 nm and where the encapsulant is epoxy mixed with a dye that absorbs radiation produced by the LED chip(s) so as to resist damage to the epoxy by radiation from the LED chip(s) while allowing desired radiation from the LED chips to pass through the encapsulant and exit the LED.  
     
     
         53 . A light emitting diode having one or more LED chips encapsulated in an encapsulate package, where the LED chip(s) have a peak emission wavelength of less than 425 nm and where the encapsulant is an acrylic.  
     
     
         54 . A light emitting diode as set forth in  claim 53  where the acrylic is polymethylmethacrylate.  
     
     
         55 . A light emitting diode having one or more LED chips encapsulated in an encapsulate package, where the LED chip(s) have a peak emission wavelength of less than 425 nm and where the encapsulant is a combination of an acrylic and polystyrene.  
     
     
         56 . A light emitting diode as set forth in  claim 53  where the encapsulant is in the form of a casting resin.  
     
     
         57 . A light emitting diode as set forth in  claim 54  where the encapsulant is in the form of a casting resin.  
     
     
         58 . The LED of  claim 48 , wherein the stabilizing agent comprises an antioxidant.  
     
     
         59 . An LED inspection lamp wherein at least one LED is the LED of  claim 11 .  
     
     
         60 . The LED of  claim 48 , further comprising additional circuitry.  
     
     
         61 . The LED of  claim 60 , wherein the additional circuitry limits or regulates current through the LED.  
     
     
         62 . The LED of  claim 48 , where the LED is a cluster LED having at least two LED chips.  
     
     
         63 . The LED of  claim 62 , wherein the cluster LED comprises: a domed region forward of each LED chip for optical purposes.  
     
     
         64 . The LED of  claim 63 , wherein the domed regions have such optical properties as to form a usably collimated beam of radiation from the LED chips without additional optics.  
     
     
         65 . The LED of  claim 63 , wherein the domed regions have such optical properties that additional optics would be used in order for a suitably collimated beam of radiation from the LED chips to be formed.  
     
     
         66 . A LED having one or more LED chips encapsulated in an encapsulant package, where the LED chip(s) have a peak emission wavelength of less than 425 nm and where the encapsulant package comprises: 
 a. an inner layer surrounding the LED chip, with said inner layer being an encapsulant material which is not damaged by ultraviolet radiation as easily as epoxy is, and    b. an outer layer which is a rigid material.    
     
     
         67 . The LED of  claim 66  wherein the inner layer of the encapsulant package is rigid.  
     
     
         68 . The LED of  claim 67  where the inner layer of the encapsulant package is in the form of a casting resin.  
     
     
         69 . The LED of  claim 68  wherein the inner layer comprises an acrylic.  
     
     
         70 . The LED of  claim 69  wherein the acrylic is polymethylmethacrylate.  
     
     
         71 . The LED of  claim 68  wherein the inner layer comprises polystyrene.  
     
     
         72 . The LED of  claim 68  wherein the inner layer comprises a polycarbonate.  
     
     
         73 . The LED of  claim 66 , wherein the LED is a cluster LED comprising at least two LED chips.  
     
     
         74 . The LED of  claim 73 , further having a domed region forward of each of the LED chips for optical purposes.  
     
     
         75 . The LED of  claim 74 , wherein the domed regions form a collimated beam of radiation from the LED chips.  
     
     
         76 . An inspection lamp, suitable for causing visible fluorescence of visibly fluorescent substances and having at least one cluster LED as set forth in  claim 62 .  
     
     
         77 . The LED inspection lamp of  claim 76 , where the LED inspection lamp further comprises the additional optics typically required to form a collimated beam of radiation from the cluster LED.  
     
     
         78 . An LED inspection lamp wherein at least one LED is the LED of  claim 66 .  
     
     
         79 . An inspection lamp, suitable for causing visible fluorescence of visibly fluorescent substances and having a cluster LED as set forth in  claim 74 .  
     
     
         80 . The LED inspection lamp of  claim 79 , further comprising additional optics, separate from the cluster LED, to form a suitably collimated beam of radiation from the cluster LED.  
     
     
         81 . An epoxy encapsulate, suitable for making LEDs having a peak wavelength of less than 425 nanometers, wherein the encapsulant comprises: a stabilizing agent to resist damage to the epoxy by radiation produced by LED chips in the LEDs.  
     
     
         82 . A LED, suitable for use in an LED inspection lamp, the LED comprising: two or more LED chips with a peak wavelength of less than 425 nanometers in a single encapsulant package.  
     
     
         83 . A LED, suitable for use in an LED inspection lamp, the LED comprising: two or more LED chips with a peak wavelength of between than 425 and 450 nanometers in a single encapsulant package.  
     
     
         84 . An LED comprising: 
 a. one or more LED chips,    b. an encapsulant for encapsulating one or more of the LED chips,    c. a stabilizing agent within the encapsulate, wherein the stabilizing agent resists degradation of the encapsulant by radiation emitted from one or more of the LED chips.    
     
     
         85 . The LED of  claim 84 , wherein the encapsulant comprises an epoxy.  
     
     
         86 . The LED of  claim 84 , wherein the stabilizing agent comprises: one or more of a phenolic inhibitor, an antioxidant, a hindered amine light stabilizer, a light stabilizer other than hindered amine light stabilizers, a light absorber that absorbs damaging wavelengths while transmitting desirable wavelengths.  
     
     
         87 . The LED of  claim 84 , wherein one or more of the LED chips emits radiation at a peak wavelength of 425 nm or less.  
     
     
         88 . The LED of  claim 84 , wherein the encapsulant comprises one or more domed regions, each domed region being forward of an LED chip.  
     
     
         89 . An LED lamp comprising: the LED of  claim 88 , and a lens forward of each domed region of the LED.  
     
     
         90 . The lamp of  claim 89 , wherein the lenses collimate the radiation from the LED into a beam.  
     
     
         91 . A flashlight comprising the LED of  claim 84 .  
     
     
         92 . An inspection lamp having light emitting diodes as a source of radiation suitable for causing visible fluorescence of fluorescent materials, where said light emitting diodes are substantially non-identical in spectral characteristics of their emitted radiation, such that at least one but not all of said light emitting diodes in said inspection lamp produce wavelengths of radiation that are favorable for causing visible fluorescence of some fluorescent materials, and such that one or more different said light emitting diodes in said inspection lamp produce substantially different wavelengths of radiation which are more favorable than the wavelengths of first said light emitting diode(s) for causing visible fluorescence of some fluorescent materials other than first said fluorescent materials.  
     
     
         93 . An inspection lamp as set forth in  claim 92  where at least one light emitting diode has a peak emission wavelength in the ultraviolet and having at least one light emitting diode with a peak emission wavelength that is visible but suitable for causing visible fluorescence of fluorescent materials.  
     
     
         94 . An inspection lamp as set forth in  claim 92  where at least one light emitting diode produces mostly blue visible light and where at least one light emitting diode produces mostly visible violet light or ultraviolet radiation.  
     
     
         95 . An inspection lamp as set forth in  claim 3  where at least one light emitting diode has a peak emission wavelength in the range of 425 to 480 nanometers and at least one light emitting diode has a peak emission wavelength in the range of 360 to 430 nanometers.  
     
     
         96 . An inspection lamp having: 
 a. Two or more light emitting diodes which produce radiation suitable for causing visible fluorescence of fluorescent materials,    b. A lens forward from each of said light emitting diodes to collimate the radiation from each light emitting diode into a beam, such that the beams of radiation individually associated with each of said light emitting diodes project forward from said lenses and merge together.    
     
     
         97 . The LED source of  claim 5 , wherein the encapsulant package is shaped to produce, for each LED chip, a beam of the radiation that is in the form of an image of each LED chip.  
     
     
         98 . The LED lamp of  claim 47 , wherein each lens projects an image of an LED chip to form a collimated beam of the radiation produced by each LED chip.  
     
     
         99 . The LED lamp of  claim 47 , wherein the LED has a round domed region forward of each LED chip, and wherein each lens projects an image of each domed region to form a collimated beam of the radiation produced by each LED chip.